CI2./3 

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HISTORY  OF 
COVERY  OF  T 
T ION  OF  THE 


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HE  Cl  R 
BLOOD 


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HISTORY 


0 F 


THE  DISCOVERY 


A LECTURE' 


B Y 

CHRISTOPHER  JOHNSTON,  M.  B. 


PROFESSOR  OP  ANATOMY, 


PUBLISHED  BY  THE  CLASS. 


B ALTIMO R E : 

PRINTED  BY  WILLIAM  K.  BOYLE. 
1867. 


HISTORY 


OF 


THE  DISCOVERY 


OF  THE 


A LECTURE 


CHRISTOPHER  JOHNSTON,  M.  D. 


PROFESSOR  OP  ANATOMY, 


PUBLISHED  BY  THIS  CLASS . 


BALTIMORE: 

PRINTED  BY  WILLIAM  K.  BOYLE. 
1867. 


of,  34-  YY)as)  $Jk  0Jcx/)4  f? 


£/2./$ 


University  of  J\J aryland, 

Baltimore,  January  14 th,  1867. 


Prof.  Christopher  Johnston, 

Sir: — Having  been  appointed  at  a meeting  of  the  Medical  Class  to  wait 
upon  you  and  request  for  publication  a copy  of  your  very  interesting  and 
instructive  Lecture  recently  delivered,  upon  the  “Discovery  of  the  Circulation 
of  the  Blood,”  we  herewith,  in  discharge  of  our  pleasant  duty,  submit  their 
wishes  to  your  consideration. 


With  much  respect, 


HENRY  T.  RENNOLDS, 
JUNIUS  L.  POWELL, 

Y.  H.  BOND, 


Committee. 


University  of  aryland , 

January  15  th,  1867. 


Messrs.  Henry  T.  Rennolds, 
Junius  L.  Powell, 


Committee. 


Y.  H.  Bond,  ) 

Gentlemen: — Your  favor  cf  14th  inst.  was  duly  received. 

I feel  greatly  flattered  by  the  kind  appreciation  with  which  the  Medical 
Class  regard  my  Lecture  on  the  Historj7  of  the  Discovery  of  the  Circulation  of 
the  Blood.  I prepared  that  Lecture  for  their  instruction;  and  it  gives  me 
much  pleasure  to  place  it  at  their  disposal. 

I have  not  deemed  it  necessary  to  cite  authorities;  but  those  who  choose 
to  consult  authors  will  learn  how  especially  I am  indebted  to  the  distinguished 
Flourens. 

With  best  wishes  for  yourselves  and  the  gentlemen  you  represent, 


I remain, 


Yours,  very  respectfully, 


CHRISTOPHER  JOHNSTON. 


’ 


' 

’ 


LECTURE. 


Gentlemen  : 

It  is  not  easy  for  you,  at  the  present  day,  to  appreciate  the 
difficulties  which  beset  the  path  of  the  older  Anatomists  and 
Physiologists.  The  field  of  science  was  wide,  much  of  it 
was  untrodden;  and  theory  took  the  place  of  experimentation 
and  observation.  There  was  more  faith  in  men  than  in  the 
age  in  which  we  live;  and  a dictum,  with  a great  name  at- 
tached, passed  current  for  truth  in  spite  of  palpable  evidence. 
Now-a-days  doctrine  is  not  accepted 'in  virtue  of  any  name, 
but  in  consequence  of  the  kind  and  amount  of  evidence  by 
which  it  is  supported. 

Again,  before  the  time  of  Vesalius  human  anatomy  was 
not  largely  cultivated  by  dissection  of  the  human  body,  nor 
permitted  to  be  practically  taught  in  public.  Wherefore, 
the  so-called  facts  in  human  Anatomy  were,  in  the  main, 
inferential,  and  were  originally  derived  from  other  and  lower 
animals  than  man 

In  our  day,  in  the  broad  sunshine  of  the  Physiology  of 
observation  and  experiment,  we  wonder  at  the  antiquated 
inductive  Physiology;  but  we  take  no  account  of  the  spirit  of 
a former  age,  and  the  very  limited  means  of  observation. 

To  understand  what  was  dimly  perceived  or  misappre- 
hended, let  me  first  express  the  modern  and  established  view 
of  the  Circulation  of  the  Blood,  and  then  we  may,  with  more 
advantage,  follow  up  the  day  from  its  dawn. 

The  adult  circulatory  apparatus  in  Mammalia — man  being 
at  the  head  of  this  class — consists  of 


6 


1st.  A double  central  and  hollow  muscular  organ;  and 

2d.  Ramified  contractile  and  elastic  tubes,  communicating 
by  their  finest  subdivisions  at  the  periphery  everywhere,  and 
with  the  central  organ  by  large  trunks. 

The  central  organ,  or  Heart,  is  divided  into  four  chambers, 
two  being  recipient  and  two  propelling  cavities.  These  are 
associated  in  pairs,  consisting  of  one  of  each  kind,  placed  one 
above  the  other,  and  constitute  single  hearts , entirely  inde- 
pendent of  each  other,  and  not  communicating , although  the 
two  hearts  are  mechanically  bound  together.  The  single 
hearts  are  named  from  their  position  right  and  left , or  venous 
and  arterial  from  the  kind  of  blood  they  respectively  receive 
and  transmit. 

Theoretically  the  two  hearts  are  adherent  along  their  con- 
tiguous sides  ; in  fact,  the  inter  auricular  and  inter  ventric- 
ular septa  are  single,  are  common  to  the  related  chambers 
which  they  sunder,  and  are  complete  and  imperforate. 

The  opening  between  the  auricle,  or  recipient  cavity,  and 
the  ventricle,  or  propelling  cavity,  of  each  single  heart,  is 
guarded  by  membraneous  valves  which  prevent  retrocession  of 
the  circulating  fluid  into  the  auricle,  and  the  orifice  of  each 
large  arterial  trunk,  aorta  and  pulmonary  artery,  is  equally 
provided  with  valves.  And  in  afferent  vessels,  or  veins , 
valves  are  placed  at  intervals  and  open  towards  the  heart. 

When  the  heart  is  in  action  the  auricles  fill,  propel  the 
blood  simultaneously  into  the  ventricles,  which  force  it 
onwards  through  the  lungs  and  into  the  system  at  large. 

Blood,  arriving  from  the  system,  reaches  the  right  ventricle 
which  projects  it  into  the  lungs,  and  returning  to  the  heart 
arterialized  or  oxygenized,  enters  the  left  auricle.  This 
circuit  is  known  as  the  lesser  or  pulmonary  circulation. 

Pressed  onwards  the  blood  fills  the  left  ventricle,  which, 
contracting,  urges  it  into  the  aorta,  whence  it  passes  through 
the  capillary  vessels  and  veins,  and  returns  to  the  right 
auricle.  This  circuit,  including  the  portal  circulation  in  a 
parenthesis,  is  the  greater  or  systemic  circulation. 

We  will  now  turn  back  to  Antiquity. 


7 


The  discovery  of  the  Circulation  of  the  Blood  does  not 
belong,  and  can,  indeed,  hardly  belong  to  one  man,  or  to  one 
epoch.  Many  errors  had  to  be  refuted;  and  for  each  error 
a truth  had  to  be  substituted.  This  was  done;  but  it  was 
accomplished  successively,  slowly,  little  by  little. 

Three  principal  errors  concealed  the  great  fact  of  the  Cir- 
culation of  the  Blood. 

1st.  That  the  arteries  contained  air  only; 

2d.  That  the  inter  ventricular  septum  was  perforated;  and 

3d.  That  the  veins  carried  Blood  to  all  parts  of  the  body, 
instead  of  bringing  it  back  from  them. 

Before  Galen  (Second  Century)  it  was  believed  on  the 
authority  of  Eristratus,  that  air,  attracted,  by  the  Lungs, 
reached  them  through  the  aspera  arteria , trachea  or  coarser 
air-tube.  Thence  the  air  passed  into  the  pulmonary  veins, 
from  these  into  the  left  ventricle;  and  from  the  left  ventricle 
it  passed  into  the  arteries,  or  air-tubes,  which  distributed  it 
to  the  system. 

Whence  an  arterial  or  air  system  ; and,  as  the  Veins  alone 
contained  Blood , a venous  or  sanguiferous  system . 

Galen,  by  experiment,  refuted  one  grand  error.  “If  we 
open  an  artery,”  says  he,  “Blood  issues,  and  as  no  air 
escapes,  the  arteries  contain  Blood.” 

He  intercepted  a portion  of  an  artery,  incised  the  included, 
part,  and  found  Blood,  but  no  air,  to  flow  out.  Wherefore 
the  arteries  contain  Blood  only. 

The  lungs  attract  air,  and  respiration  serves  to  refresh 
the  blood. 

Galen  believed,  however,  that  the  ventricular  septum  was 
perforated,  and  that  the  veins  carried  the  blood  into  the 
system. 

That  there  were  two  sorts  of  Blood,  the  spirituous , nourish- 
ing such  delicate  organs  as  the  Lungs;  and  the  Venous, 
nourishing  such  gross  organs,  as  the  Liver. 

The  pure  spirit  was  generated  in  the  Left  Ventricle,  but  a 
portion  passed  through  the  septal  pores  into  the  venous 
Blood  of  the  Right  Ventricle. 


8 


He  also  taught  that  arterial  pulsation  was  due  to  a pulsific 
virtue  iu  the  arteries,  derived  through  their  tuuics  from  the 
heart. 

But  his  great  doctrine  was  that  the  chyle  was  taken 
up  by  the  intestine  veins,  carried  by  them  into  the  Liver , 
(towards  the  centre !)  and  there  changed  into  Blood.  The 
Liver  then,  was  the  organ  for  the  conversion  of  chyle  into 
Blood , the  organ  for  the  conversion  of  black  blood  into  red 
blood.  The  Liver  was,  in  fact,  the  organ  of  Sanguification. 

And  to  complete  a symmetrical  physiology,  Galen  main- 
tained that  the  Brain  is  the  origin  of  all  the  nerves;  the 
Heart , the  origin  of  all  the  arteries,  and  the  Liver , the 
origin  of  all  the  veins. 

For  nearly  fourteen  hundred  years  these  same  doctrines 
held  ground  even  in  the  face  of  direct  observation,  against 
which  it  was  thought  sufficient  to  assert  “Dixit  Galenus.” 
Even  Andreas  Vesalius,  after  satisfying  himself  of  the  non- 
existence of  the  assumed  inter-ventricular  foramina , speaks 
of  the  passage  of  blood  through  them,  as  he  says,  to  accom- 
modate himself  to  the  dogmas  of  Galen. 

But,  at  length,  unable  any  longer  to  resist  the  truth,  he 
affirmed  that  the  septum  was  not  perforated;  and  a second, 
error  vanished.  But  the  third  error,  viz : that  the  veins 
carried  blood  towards  and  to  the  extreme  parts  was  still 
retained,  although,  even  in  the  time  of  Galen,  venesection 
was  practiced,  and  the  vein  was  seen  to  swell  below  the  liga- 
ture, where  it  was  punctured. 

Michael  Servetus,  in  a tract  entitled  “Christianismi  Resti- 
tutio/ ’ (A.  D.  1553)  describes  the  Pulmonary  Circulation; 
and  this  is  the  manner  in  which  so  strange  a mixture  of 
physiology  and  theology  came  to  pass. 

Servetus  was  a matter-of-fact  man.  In  Scripture  he  found 
it  written,  “Anirna  est  in  Sanguine;  anima  ipsa  est  San- 
guis.” Since  the  soul  is  in  the  blood,  says  Servetus  to  him- 
self, to  know  how  the  soul  is  formed  we  must  find  out  how 
the  blood  is  formed;  to  know  how  the  blood  is  formed,  we 
must  see  how  it  moves;  and  thus  in  connection  with  the 


9 


revival  of  Christianity , he  is  led  to  the  formation  of  the 
Soul,  from  this  to  the  formation  of  the  Blood,  and  thence  to 
the  Pulmonary  Circulation. 

For  his  religious  tenets  he  was  burned  with  his  books,  by 
Calvin,  in  Geneva,  in  1553,  October  27th. 

Servetus  denied  the  inter-ventricular  pores  or  canals,  but 
asserted  that  the  blood  took  a longer  course  through  the  pul- 
monary artery  into  the  lung,  where  it  is  agitated,  prepared, 
and  where  it  becomes  red,  and  passes  from  the  pulmonary 
artery  into  the  pulmonary  veins.  And  he  gives  as  a reason, 
a very  fine  one,  too,  for  the  communication.  The  pulmo- 
nary artery,  says  he,  would  not  be  so  large — would  not  con- 
vey so  great  a quantity  of  blood  to  the  lungs — if  its  office 
were  only  to  nourish  the  pulmonary  tissue;  for,  in  the  embryo 
the  lungs  derive  nourishment  elsewhere,  since  blood  does 
not  reach  them  by  this  source. 

And  in  another  place  he  says:  “In  the  same  manner 
that  in  the  Liver  the  passage  of  blood  takes  place  from  the 
portal  vein  into  the  vena  cava,  so  also  in  the  lung  is  effected 
the  transfusion  of  blood  from  the  arterial  vein  (pulmonary 
artery)  into  the  venous  artery  (pulmonary  vein). 

A step  farther,  and  the  discovery  of  the  double  circulation 
of  the  blood  would  have  been  made. 

Six  years  after  Servetus.  Realdo  Columbo,  of  Padua,  dis  • 
covered  the  fact  of  the  pulmonary  circulation  independently; 
and  in  1593,  in  Venice,  Andreas  Ceesalpinus,  also  of  Padua, 
described,  as  a discovery  of  his  own,  the  passage  of  the  blood 
from  the  right  heart  through  the  lungs  to  the  left  heart,  and 
applied  to  this  passage  the  very  word  Circulation. 

But  he  does  not  stop  at  the  lesser  circle — lie  goes  further. 
Cesalpin,  who  first  noticed  that  the  veins,  in  venesection, 
swell  beyond  the  ligature,  expresses  his  astonishment  at  the 
circumstance,  when  all  dogmas  affirmed  that  the  blood  flowed 
in  the  veins  from  the  centre  to  the  periphery.  And  he  then 
asserts  that  “The  Blood,'  borne  to  the  heart  by  the  veins , receives 
in  that  organ  its  last  perfection;  and  this  supreme  quality 
acquired,  it  is  carried  by  the  arteries  into  the  body  every- 
where. 


10 


He  traces  the  blood  in  its  course  from  the  vena  cava 
through  the  heart  into  the  lungs,  thence  into  the  left  ventri. 
cle,  and  finally  into  the  aorta,  around  the  mouth  of  which 
and  the  pulmonary  artery  he  described  ‘ 1 certain  membranes  ” 
so  adjusted  as  to  prevent  retrocession.  And  then  there  is 
a perpetual  certain  motion  from  the  vena  cava  through  the 
heart  and  lungs  into  the  aorta. 

And,  to  repeat,  we  first  meet  in  Cesalpinus  with  the  dis- 
tinct expression,  Circulation  of  the  Blood. 

The  idea  was  expressed,  but  it  remained  fruitless  with 
Cesalpin,  who  neither  appreciated  its  force  nor  its  conse- 
quence. 

It  may  well  be  regarded  as  surprising  that  as  error  after 
error  was  disembowelled  and  cast  aside,  and  a sterling  truth 
substituted  for  each  error — that  with  the  actual  fact  of  the 
lesser  and  the  greater  circulations  pointed  out — there  should 
still  be  required  anything  but  the  acceptance  of  the  great 
fact  in  science.  And  this,  too,  when  Fabricius  d’Acquapen- 
dente,  in  Italy,  and  a Professor  in  Padua,  had  already,  in 
1574,  made  the  discovery  of  the  valves  of  the  veins — had 
even  found  that  they  opposed  the  course  of  the  blood  from 
the  heart,  that  the  blood  must  proceed  to  and  towards  the 
heart,  inversely  to  what  happens  in  the  arteries,  which  have 
no  valves.  Fabricius  was  even  the  master  of  Haivey,  who 
studied  in  Padua. 

The  different  'parts  of  the  circulation  had  been  discovered, 
but  the  parts  remained  separate,  disjoined  and  unprofitable. 
In  this  discovery,  (says  Flourens)  the  difficult  point  was  to 
connect  the  divers  parts,  and,  if  I may  so  express  myself, 
the  various  pieces,  successively  brought  to  view,  into  a 
unity — the  difficult  point  was  to  seize  the  comprehensive 
whole  of  the  phenomenon,  of  the  mechanism.  And  it  is 
because  Hai  vey  is  the  first  who  did  so  grasp,  clearly  and 
completely,  the  phenomenon  in  its  entireness,  that  the  great 
glory  has  been  awarded  to  him. 

Michael  Servetus,  to  whom  the  discovery  of  the  pulmonary, 
or  lesser  circulation  is  attributed,  made,  perhaps,  a wider 
step  towards  the  great  truth  than  any  of  his  predecessors. 


J1 


As  his  name  deserves  and  receives  mention  in  connection 
with  the  Circulation  of  the  Blood,  a word  as  to  his  life  and 
unfortunate  end  may  not  be  considered  out  of  place. 

Michael  Servetus  was  a native  of  Arragon,  in  Spain,  and  the 
son  of  a Notary.  He  studied  Law  at  Toulouse;  but  manifest- 
ing a stronger  affection  for  Medicine,  he  studied  at  Paris,  took 
the  Doctor’s  degree,  and  subsequently  established  himself  as 
a practitioner  of  medicine  in  Dauphiny.  Not  content  to  seek 
celebrity  in  medical  pursuits,  and  eager  to  publish  his  Arian 
religious  opinions,  he  sent  three  “questions”  to  Calviu, 
(who  maybe  said  to  have  ruled  in  Geneva)  “on  the  Divinity 
of  Christ,”  “on  Regeneration,”  and  “on  the  necessity  of 
Baptism.”  His  ardent  disposition  changed  the  peaceful 
temper  of  the  controversy  he  had  begun  into  a bitter  corres- 
pondence; and  Calvin  became,  in  consequence,  his  unrelent- 
ing foe. 

In  1553  Servetus  published  a book  embracing  most  of  his 
previous  writings,  and  which  had  this  title:  “Christianismi 
Restitutio,”  the  revival  of  Christianity;  whereupon  Calvin 
caused  him  to  be  accused  as  a dangerous  man,  and  his 
imprisonment  soon  followed.  Escaped  from  prison,  he 
attempted  to  pass  through  Geneva  in  disguise,  but  was 
seized  by  the  authorities  as  an  impious  heretic.  The  Magis- 
trates, urged  especially  by  Calvin,  condemned  their  prisoner 
as  guilty  of  forty  heretical  errors;  and  upon  his  refusing  to 
renounce  them,  was  burnt  at  the  stake  a few  months  after 
the  publication  of  his  book,  on  the  27th  of  October,  1553, 
and  died  after  two  hours  torture. 

The  only  two  copies  of  this  remarkable  work  belong  to  the 
imperial  libraries  of  Paris  and  Vienna  ; and  that  of  Paris  is 
the  very  same  which  was  used  by  Colladon,  one  of  the 
accusers  instigated  by  the  implacable  Calvin  against  Servetus. 
Colladon,  underlined  the  propositions  which  served  as  the 
basis  of  the  accusation;  and  this  volume,  somewhat  scorched 
by  fire,  was  only  snatched  from  the  pile  upon  which  the 
author  and  his  books  were  to  be  burned,  when  the  flames  had 
already  begun  to  ascend. 


12 


When  Harvery  appeared,  everything  relating  to  the  Circu- 
lation of'  the  Blood  had  been  suggested  or  suspected,  but 
nothing  was  established.  Servetus  had  pointed  out  the  lesser 
circulation,  hut  knew  nothing  of  the  greater.  Columbo  had 
done  nearly  the  same,  but  he  adhered  to  the  doctrine  of  Galen 
that  the  veins  arise  in  the  liver  and  convey  blood  to  the 
periphery.  Cesalpinus,  who  sees  the  two  circulations,  retains 
the  error  of  antiquity  that  the  ventricular  septum  is  perfo- 
rated. And  finally  Fabricius  discovers  the  valves  of  the 
veins,  but  knows  nothing  about  the  circulation.  None  of 
them  had  an  idea  of  the  torrent  of  blood  which  traverses  the 
pulmonary  artery  and  veins  in  a given  time.  And  if  they 
had  conceived  it,  they  would  have  been  sorely  embarrassed  to 
tell  whence  that  blood  came,  and  whither  it  went. 

Harvey  begins  with  the  motions  of  the  double  Heart , and 
observes  that  the  auricle  and  ventricle  of  each  heart  contract 
successively.  When  the  auricles  contract,  (being  filled  by 
the  veins,)  they  pour  their  blood  into  the  ventricles,  which 
then  propel  their  blood  into  the  lungs , on  the  one  hand,  and 
into  the  system  at  large  on  the  other;  and  he  lays  stress  on 
the  fact  that  the  aortic  and  pulmonary  orifices  are  guarded 
by  “little  gates,”  “ostiola,”  or  valves,  which  prevent  regur- 
gitation during  the  diastole  of  the  ventricles. 

Then  he  proceeds  to  show  that  the  arterial  'pulse  is  due  to 
the  distending  force  of  the  blood  urged  by  the  heart;  and 
proves,  by  opening  an  artery  in  a living  animal,  that  while 
the  blood  issues  in  jets,  these  are  strongest  in  the  diastole  (or 
distension)  of  the  artery  than  during  its  systole. 

Harvey  also  noticed,  in  connection  with  arteriotomy , that 
all  the  blood  (as  he  expresses  it)  of  an  animal  will  flow  out  of 
a wounded  artery;  wherefore  heart,  arteries  and  veins  must 
communicate  with  one  another. 

How  could  it  be  otherwise,  in  view  of  the  great  rapidity  of 
the  circulation?  says  the  great  Englishman  who  now  makes 
that  celebrated  calculation.  Suppose  that  the  heart  propels, 
at  each  pulsation,  three  ounces  of  blood,  of  which  the  valves 
prevent  the  retrocession,  that  heart  which  in  a half  hour 
makes  more  than  a thousand  pulsations,  and  sometimes  even 


18 


four  thousand.  In  a half  hour,  therefore,  more  than  five 
hundred  ounces  of  blood  will  pass  from  the  arteries  into  the 
veins  , a mass  more  considerable  than  the  entire  capacity  of 
the  body. 

If,  instead  of  a half  hour  we  suppose  an  hour,  a day , the 
quantity  which  would  pass  through  the  heart  would  be 
greater  than  could  be  furnished  by  the  food  in  the  same 
period.  Wherefore  the  blood  passes  not  once,  but  several 
times  through  the  heart  in  a given  time.  (Exercitationes, 
page  89.) 

From  the  arteries  Harvey  proceeds  to  the  veins , and  draws 
full  consequences  from  the  fact  that  their  valves  open  in  one 
direction  only,  and  allow  a current  tendTng  towards  the  heart. 
He  constricts  a member  slightly,  and  the  veins,  being  super- 
ficial, swell  up — he  firmly  binds  the  member,  and  the  course 
of  the  blood  is  arrested  because  the  deeper  seated  arteries  are 
compressed. 

When  he  ties  a vein,  it  swells  below  or  beyond  the  liga- 
ture; if  an  artery,  it  dilates  above  the  ligature.  The  blood, 
therefore,  moves  in  the  veins  and  in  the  arteries  in  opposite 
directions;  in  the  veins  it  courses  from  the  body  to  the  heart, 
and  in  the  arteries  it  flows  from  the  heart  into  the  body 
every where.  This  movement,  this  continual  exit  and  return 
of  the  Blood  is  the  Circulation. 

William  Harvey  was  born  (in  England  as  you  are  all 
aware)  April  2d,  1578.  At  the  age  of  nineteen  he  travelled 
through  France  and  Germany,  and,  attracted  by  the  repu- 
tation of  Fabricius  d’ Acquapendente,  he  proceeded  to 
Padua,  and  applied  himself  to  the  study  of  Medicine  under 
that  great  master.  He  returned  to  London  with  all  the 
information  upon  the  subject  of  the  circulation  of  the  blood 
which  could  then  be  gathered.  In  1615  he  was  made  Lec- 
turer on  Anatomy  and  Surgery;  in  1616  he  laid  open  the 
discovery  of  the  circulation  of  the  blood  in  his  lectures,  and 
in  1728  his  famous  “Exercetatio  Anatomica  de  Motu  Cordis 
and  Sanguinis/’  his  masterpiece,  and  dedicated  the  work  to 
Charles  II  after  having  verified  the  statements  it  contained 
by  many  years  experiments. 


14 


Having,  then,  says  the  distinguised  Flourens,  demonstrated 
the  circulation  of  the  blood;  but  he  comes  from  Padua , 
where  he  had  for  his  master  Fabricius,  of  Acquapendente, 
who  had  discovered  the  valves  in  the  veins ; but  in  this  same 
University  of  Padua , where  the  first  germ  of  all  Harvey’s 
ideas  had  its  birth,  Realdo  Columbo  had  recently  held  a 
Professor’s  Chair,  he  who,  six  years  subsequently  to  Ser- 
vetus,  had  discovered  the  pulmonary  circulation;  and  not  far 
from  Padua  lies  Pisa , where  Cesalpin,  in  a burst  of  genius, 
more  than  suspected  the  pulmonary  circulation,  and  in 
another  inspiration  perceived  the  general  circulation. 

All,  however,  was^  rude,  vague  and  unsettled— all  doc- 
trines were  discordant;  and  it  is  the  great  glory  of  Harvey 
that  he  brought  order  out  of  chaos,  that  he  held  fast  to  truth 
and  made  it  his  own — that  he  found  his  truth  in  observation 
and  established  it  by  experiment — thus  practically  he  dis- 
covered the  most  beautiful  phenomenon  of  the  animal  econ- 
omy. Men  no  longer  swore  by  Galen , they  swore  by  Harvey. 


The  circulation  of  the  blood,  the  passage  of  the  blood  from 
the  arteries  into  the  veins,  had  been  proven  and  established 
as  a fact  by  Harvey,  but  the  direct  demonstration  was  want- 
ing. It  came  at  last,  the  microscope  afforded  it;  but  it  was 
denied  to  the  grand  old  age  of  Harvey,  who  died  without 
witnessing  it.  In  1661  Malpighi  saw  the  blood  pass  from 
the  arteries  into  the  veins  in  the  mesentry,  the  lung  and  the 
urinary  bladder  of  frogs.  The  matter  was  still  more  clearly 
exposed  in  1668  by  Leeuwenhoeck,  and  later  still  by  G.  Cow- 
per.  So  that  now,  against  ocular  demonstration , objection 
raised  its  voice  in  vain. 


The  Sixteenth  Century,  gentlemen,  was  a noble  era  in 
art  and  science.  It  was  the  age  of  Raphael,  Michael  Angelo, 
and  Leonardo  da  Vinci — of  Titian,  Guido  and  Corregio — 
Ariosto  and  Tasso  sang  with  inspired  lips,  and  Shakspeare, 


15 


Prometheus  like,  stole  fire  from  heaven  to  vivify  his  crea- 
tions. Artillery  was  first  used,  and  modern  warfare  had 
thus  its  beginning  under  Francis  I.  at  the  commencement  of 
this  century;  and  the  silken  ligature , invented  by  the  re- 
nowned Ambrose  Pare,  towards  its  conclusion,  first  arrested 
hemorrhage.  The  microscope  and  telescope  were  sketched 
out  just  before  the  close  of  this  epoch;  while  in  the  very 
middle  of  the  Sixteenth  Century  the  circulation  of  the  blood 
was  first  announced  to  the  world.  But  the  real  discovery  of 
the  circulation,  of  the  circulation  of  the  blood  as  a practical, 
substantial  thing,  as  the  starting  point  of  Modern  Physi- 
ology, was  reserved  for  Harvey,  the  Great  Harvey,  in  the 
beginning  of  the  Seventeenth  Century. 


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Syracuse,  N.  Y. 
Stockton,  Calif. 


